In plasma processing of a workpiece such as a semiconductor wafer, mask, flat panel display or solar cell, an inductively coupled plasma source can provide a high density plasma. An inductively coupled plasma source typical includes an RF power generator furnishing power through an impedance match and an inductively coupled source power applicator such as a coiled conductor or coil antenna. Such a coil antenna typically overlies the chamber ceiling, giving rise to certain problems. One problem is that a coil antenna configured to uniformly cover the processing zone (e.g., the area of the workpiece or wafer) necessarily has a significant amount of undesirable capacitive coupled RF voltage to the plasma. Such a coil antenna has a large voltage drop across its terminals when a high level of RF source power is applied, increasing the risk of arcing, and sputtering underneath. Another problem is that the ceiling must be formed of an insulating material to permit inductive coupling of RF power from the coil antenna into the chamber interior. Restricting the ceiling to insulating materials prevents use of the ceiling as a grounded return electrode, so that the effective grounded electrode area is limited to the chamber side wall. Restricting the ceiling to insulating materials makes it impractical for the ceiling to be configured as a gas distribution showerhead, so that process gas must be injected from the side, limiting the uniformity of gas distribution over the wafer. Finally, the efficiency of an overhead coil antenna is limited because it is displaced above the ion generation region.